#import <objc/objc.h>
#import <objc/Object.h>
 
@interface TestObj
@end
 
@implementation TestObj
int main() {
	// your code goes here
	const char* test = "hello";
 
	//compilation error:
	//test[2] = '1';
	//printf("%s", test);
 
	//runtime error:
	//char* test2 = test;
	//test2[2] = '1';
	//printf("%s", test2);
 
	//no error
	int len = strlen(test);
	char* copy = malloc(len + 1);
	strcpy(copy, test);
	copy[2] = '1';
	printf("%s", copy);
 
	free(copy);
	return 0;
}
@end

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